1. Field of the Invention
The invention relates generally to meter centers for electrical power distribution systems and, more particularly, to base assemblies for the meter socket assemblies of meter centers. The invention also relates to meter socket assemblies for meter centers.
2. Background Information
Meter centers including a number of watt-hour meters are commonly used to measure electric power consumed by the tenant(s) of a residence (e.g., without limitation, a single family home; an apartment building) or commercial site (e.g., without limitation, an office complex).
FIGS. 1A and 1B show an example meter center 1. The meter center 1 includes an upright cabinet forming an enclosure 3. The enclosure 3 is divided by an internal longitudinal wall 5 into side-by-side meter and disconnect switch compartments 7,9 (disconnect switch compartment 9 is shown in FIG. 1A only). A pair of vertical supply buses 11A,11B (FIG. 1A) are electrically connected at one end to a meter socket assembly 13 within the meter compartment 7 and, at the other end, to an electrical switching apparatus, such as the circuit breaker 15 shown in FIG. 1A, within the disconnect switch compartment 9. The meter socket assembly 13 includes a meter socket 17 (FIG. 1B) for mounting a meter 19 (FIG. 1B) in the meter compartment 7 for each tenant load circuit, and to electrically connect the meter 19 (FIG. 1B) to line buses 21A, 21B (line bus 21A is shown in FIG. 1A only) which are electrically connected to the respective supply buses 11A,11B (FIG. 1A). Meter centers and electrical bus work therefor are described in detail, for example, in U.S. Pat. No. 6,012,937 (Campbell et al.), which is hereby incorporated herein by reference.
The meter socket assembly 13 of FIGS. 1A and 1B is designed to be interchangeable between an underground feed configuration (shown), and an overhead feed configuration (not shown). In the underground feed configuration, the utility lines (not shown) are routed to the meter center 1 underground and are typically fed through the bottom (from the perspective of FIGS. 1A and 1B) of the meter center enclosure 3 to be electrically connected at or about the lower end (from the perspective of FIGS. 1A and 1B) of the line buses 21A,21B (line bus 21A is shown in FIG. 1A only). In an overhead feed configuration, the utility lines (not shown) are routed to the meter center 1 above ground and are fed through the top (from the perspective of FIGS. 1A and 1B) of the meter center enclosure 3 to be electrically connected to the upper end (from the perspective of FIGS. 1A and 1B) of the line buses 21A,21B.
Each line bus 21A,21B has two twisted sections of about 90 degrees each, in order that the upper and lower ends of the line buses 21A,21B are horizontal (with respect to the plane of the back panel 27 of the meter cabinet 3) and the middle portions of the buses 21A,21B are vertical (with respect to the plane of the back panel 27 of the meter cabinet 3). As best shown in FIG. 1A, the vertical portion of each of the line buses 21A,21B is side mounted to a corresponding individual base member 23A,23B by a pair of side-mount screws 25. These separate sub-assemblies, which together form the meter socket assembly 13, are then mounted to the back panel 27 of the meter cabinet 3 by first and second pedestal assemblies 29,31 (FIG. 1B). Each pedestal assembly 29,31 comprises multiple components and employs a plurality of fasteners 33. The first and second pedestal assemblies 29,31 are disposed at the upper (from the perspective of FIGS. 1A and 1B) and lower (from the perspective of FIGS. 1A and 1B) ends of the line buses 21A,21B, respectively. In addition to functioning as mounting brackets for mounting the meter socket assembly 13, the pedestal assemblies 29,31 also serve to support the line buses 21A,21B. A still further number of fasteners 35 (FIG. 1B) are required to secure wire connectors, commonly referred to as lugs 37, to the line buses 21A,21B for providing the electrical connection between the meter socket assembly 13 and, for example, the utility lines (not shown).
Accordingly, the meter socket assembly 13 has numerous separate components and fasteners 25,33,35 therefor. This makes assembly, repair, replacement, and/or maintenance of the meter socket assembly 13 difficult. For example, removal or replacement of the line buses 21A,21B would require the side-mount screws 25 (FIG. 1A) to be removed in four locations, the lug fasteners 35 and lugs 37 to be removed in two locations, and the line buses 21A,21B to be disengaged from both of the pedestals 29,31. The fasteners 25,33,35 could be lost and/or can strip or break during the above removal or replacement process. Also, access to some of the fasteners, such as the aforementioned side-mount fasteners 25 (FIG. 1A), is limited, and can require special tools to be used to loosen or tighten them. Furthermore, the twisted structure of the line buses 21A,21B unnecessarily uses more material than required.
There is, therefore, room for improvement in meter centers and in meter socket assemblies therefor.